Film loader for an image forming apparatus

ABSTRACT

A film loader for the image forming apparatus has a film formed endlessly and a film frame for holding the film, wherein a guide member for attaching or detaching the film with respect to the film loading portion of the film frame is formed by a packaging member for use in transporting and storing the film.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a film loader for an imageforming apparatus, and more particularly to the loading of a film suchas a photosensitive film, an intermediate transfer film, a transferfilm, a carrier film or a fixing film to be used in each portion of anelectrophotographic printer.

[0003] 2. Description of the Related Art

[0004] A conventional film loading method includes steps of detaching afilm frame from a main body of an image forming apparatus, placing thefilm frame vertically, loading a photosensitive film into the film framelongitudinally from above, and thereafter attaching the film frame tothe main body of the image forming apparatus.

[0005]FIG. 12 is a schematic view of the film loader with aphotosensitive film loaded in the related art. In FIG. 12, referencenumeral 1 denotes the photosensitive film, reference numeral 5 denotesthe film frame, and reference numerals 6 a and 6 b denote holdingrollers for holding the photosensitive film 1. In loading thephotosensitive film 1, while the photosensitive film 1 is supported byan operator's hand in a state where the film frame 5 is drawnhorizontally from the main body not shown, the photosensitive film 1 isaligned with the film frame 5 and the holding rollers 6 a and 6 b andthen loaded into the film frame 5.

[0006] In this operation, the operator conducts the replacement of thephotosensitive film while the operator touches only an inner backingportion of the film or end portions of the film surface (both of annularedge portions), but does not touch the surface of the photosensitivefilm or wears globes.

[0007] In the related art where the film frame is vertically placed, itis necessary to detach the film frame from the main body of the imageforming apparatus. The film frame is a heavy substance, and there arisesproblems in the respects of operability and maintenance.

[0008] Also, in the related art where the photosensitive film is loadedinto the film frame horizontally drawn from the main body of theapparatus by an operator's hand, it is impossible to repair a slack inthe central part of the film when loading, causing a bend or a crack inthe photosensitive film, resulting in a problem that the photosensitivefilm is damaged on the surface and unusable.

[0009] Particularly, the latest image forming apparatus with very highprocessing speed has a peripheral length of the photosensitive film of 2m or more, and a length in the depth direction (drawing direction inloading) of 60 cm or more, whereby some skills are required to load thefilm into the film load because two operators are difficult to load thefilm there into.

SUMMARY OF THE INVENTION

[0010] The present invention has been made in view of the abovecircumstances, and therefore an object of the invention is to provide afilm loader for an image forming apparatus which makes it possible toreadily load a film without damaging the film surface.

[0011] To achieve the above object, according to one aspect of thisinvention, there is provided a film loader for an image formingapparatus comprising a film formed endlessly, a film frame for holdingthe film, and a guide member for guiding the film at the time of loadingor detaching the film, the guide member serving as a packaging member tobe used in transporting or storing the film.

[0012] The guide member may be shaped in a pipe having two or more axlesprovided detachably in the film loading portion of the film frame.

[0013] The film loader may further comprise an adaptor through which thepipe member is fixed to the film frame.

[0014] The guide member may be detachably attached to the centralportion of the film loading portion of the film frame.

[0015] According to another aspect of this invention, there is provideda film loader for an image forming apparatus, comprising a film formedendlessly, a film frame for holding the film, and a guide member havinga smaller width than the film, the guide member being detachablydisposed in a film loading portion of the film frame.

[0016] The guide member may be shaped in a pipe having two or more axlesprovided detachably in the film loading portion of the film frame.

[0017] The guide member may comprise a packaging member to be used intransporting or storing the film.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] These and other objects and advantages of this invention willbecome more fully apparent from the following detailed description takenwith the accompanying drawings in which:

[0019]FIG. 1 is a schematic view of a film loader with a photosensitivefilm loaded according to the present invention;

[0020]FIG. 2 is a cross-sectional view of an attaching portion between aguide plate and a film plate according to the embodiment of thisinvention;

[0021]FIG. 3 is a schematic view of the film loader with thephotosensitive film packaged according to another embodiment of theinvention;

[0022]FIG. 4 is a schematic view of a film loader according to anotherembodiment of the invention;

[0023]FIG. 5 is a cross-sectional view of an attaching portion betweenthe guide plate and the film plate according to this invention;

[0024]FIG. 6 is a cross-sectional view of an attaching portion betweenthe guide plate and the film plate according to this invention;

[0025]FIG. 7 is a schematic view of a film loader according to anotherembodiment of the invention;

[0026]FIG. 8 is a cross-sectional view of an attaching portion betweenthe guide plate and the film plate according to this invention;

[0027]FIG. 9 is a schematic view of a film loader according to anotherembodiment of the invention;

[0028]FIG. 10 is a cross-sectional view of an attaching portion betweenthe guide plate and the film plate according to this invention.

[0029]FIG. 11 is a schematic view of an image forming apparatus to whichthe invention is applied; and

[0030]FIG. 12 is a schematic view of a conventional film loader with aphotosensitive film loaded.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Now, a description will be given in more detail of preferredembodiments of the invention with reference to the accompanyingdrawings.

[0032] In the following description, a photosensitive film is employed,but the invention is not limited to thereto, and the invention may beapplied to an intermediate transfer body, a transfer film, a carrierfilm and a fixing film besides the photosensitive film.

[0033] (First Embodiment)

[0034]FIG. 1 is a schematic view of a film loader for an image formingapparatus according to an embodiment of the invention. In FIG. 1,reference numeral 1 denotes a photosensitive film, 2 a and 2 b arepipes, 3 a and 3 b are adaptors, 4 is a guide member, 5 is a film frame,and 6 a and 6 b are holding rollers.

[0035] In loading the photosensitive film 1, the film frame 5 is drawnhorizontally from a main body of the apparatus not shown, the adaptors 3a, 3 b and the guide member 4 are attached to the film frame 5 as shownin FIG. 1, and thereafter the pipes 2 a and 2 b around which thephotosensitive film 1 is put are fitted to the adaptors 3 a and 3 b,thereby supporting the photosensitive film 1. The guide member 4 istapered such that when an operator loads the film loader with thephotosensitive film 1, a slack occurring in the center of thephotosensitive film 1 is eliminated along the taper of the guide member4. Also, because the photosensitive film 1 is supported by the pipes 2 aand 2 b, the photosensitive film 1 can be prevented from dropping down.Accordingly, the photosensitive film 1 can be readily loaded into thefilm loader without damaging the surface of the photosensitive film 1.In this case, the pipes 2 a and 2 b must be securely fitted to theadaptors 3 a and 3 b, and the adaptors 3 a and 3 b must be securelyfitted to the film frame 5, respectively, as shown in FIG. 2.

[0036] In FIG. 2, reference numeral 2 denotes a pipe, reference numeral3 denotes an adaptor, reference numeral 5 denotes a film frame,reference numeral 6 denotes a support roller, and reference numeral 7denotes a flange. The flange 7 is so designed as to rotatably fit thesupport roller 6 to the film frame 5. The adaptor 3 and the flange 7 arescrewed such that they can be securely fixed to each other so as toprevent the adaptor 3 from dropping down.

[0037] A leading end portion of the adaptor 3 is tapered so that thepipe 2 can be readily inserted into the adaptor 3. The dimensionalrelation between an inner diameter D1 of the pipe 2 and an outerdiameter D2 of the adaptor 3 is placed in clearance fit, and because theouter diameter D2 of the adaptor 3 ensures a length sufficient to fitthe pipe 2 substantially horizontally, the pipe 2 can be surely fittedinto the adaptor 3.

[0038] The pipes 2 a and 2 b in FIG. 1 are package members used fortransport and storage of the photosensitive film as shown in FIG. 3. Thepipes 2 a and 2 b as the package members are made of, for example,paper, resin or metal such as aluminum. Paper is superior from theviewpoints of low costs, lightweight and disposal. Also, resin issuperior from the viewpoints of lightweight and high strength, and metalsuch as aluminum is superior from the viewpoint of high strength. Amongthose materials, paper pipes are most preferable to this invention.

[0039] Referring to FIG. 3, reference 1 denotes a photosensitive film, 2a and 2 are pipes, 8 is a container box, and 9 a and 9 b are pipe fixingmembers. The photosensitive film 1 is supported by the pipes 2 a and 2b, and then fixed on the pipe fixing members 9 a and 9 b in such amanner that the surfaces of the photosensitive film 1 are completely outof contact with the interior of the container box 8.

[0040] In taking out the photosensitive film 1 from the container box 8,an operator holds end portions 10 a and 10 b of the pipes 2 a and 2 b,and then takes out the photosensitive film 1 and the pipes 2 a and 2 btogether. This makes it unnecessary that the operator touches thesurface of the photosensitive film 1 with his hand. As a result, theoperator can take out the photosensitive film 1 from the container box 8without damaging the surface of the photosensitive film 1.

[0041] Referring to FIG. 11, the overall constitution of theabove-mentioned image forming apparatus with the photosensitive filmloaded will be described below.

[0042] A printing unit 18 a includes a photosensitive film 19 a, anelectrifier 20 a, an exposing unit 21 a, a developing unit 22 a, atransfer unit 23 a, and a cleaner 24 a. Printing units 18 b to 18 d areidentical in construction with the printing unit 18 a.

[0043] The printing units 18 a to 18 d make the printing of differentcolors on a sheet 25, for example, the printing unit 18 a for yellow,the printing unit 18 b for magenta, the printing unit 18 c for cyan, andthe printing unit 18 d for black.

[0044] The printing operation of the printing unit 18 a will bedescribed below. The photosensitive film 19 a starts to rotate on thebasis of a printing operation start signal from a controller not shown,rotates at a rate corresponding to a print speed, and continues torotate until the printing operation is completed. Upon starting torotate the photosensitive film 19 a, a high voltage is applied to theelectrifier 20 a so that the surface of the photosensitive film 19 a isevenly electrified with positive charges.

[0045] The character data or graphic data converted into dot images issent from the controller not shown to the image forming apparatus withanon/off signal of the exposing unit 21 a, thereby forming an irradiatedportion and a non-irradiated portion by the laser beam on the surface ofthe photosensitive film 19 a by the exposing unit 21 a. A portion wherecharges disappear on the photosensitive film 19 a comes to a positionopposed to the developing unit 22 a by irradiation of the laser beamfrom the exposing unit 21 a, the toner electrified with positive chargesis absorbed by static electricity to form a toner image on thephotosensitive film 19 a.

[0046] The sheet 25 is conveyed in synchronism with a timing when theprint data formed on the photosensitive film 19 a reaches a transferposition. The toner image formed on the photosensitive film 16 a issucked onto the sheet 25 due to an action of the transfer unit 23 a thatattaches charges of reverse polarity to the toner image onto the backside of the sheet 25. The photosensitive film 19 a that has passedthrough the transfer position is cleaned by the cleaner 24 a, and aresidual toner on the photosensitive film 19 a is absorbed by a suctionblower not shown, and recovered into a recovery unit not shown, toprepare for the next printing operation.

[0047] The sheet 25 having passed through the printing unit 18 a issubjected to the same printing operation in the printing units 18 b, 18c and 18 d, and conveyed to the fixing unit 26. The toner image on thesheet 25 that has reached the fixing unit 26 is molten and fixed on thesheet 25.

[0048] The photosensitive films 19 a, 19 b, 19 c and 19 d aredeteriorated by repeating the printing operation and therefore must beexchanged periodically.

[0049] Thus, using the film loader of the invention, the photosensitivefilm is easily loaded without detaching the film frame from the mainbody of the image forming apparatus and without damaging the surface ofthe photosensitive film by the operator. As a result, it is unnecessaryto make an operation of removing the film frame every time thephotosensitive film is exchanged, and it is possible to avoid damagingthe surface of the photosensitive film before starting the printingoperation to make the photosensitive film unusable.

[0050] (Second Embodiment)

[0051]FIG. 4 is a schematic view showing another embodiment of theinvention.

[0052] In FIG. 4, in loading the photosensitive film 1, the film frame 5is drawn horizontally from the main body of the apparatus, thephotosensitive film 1 is put around the pipes 2 a and 2 b, and the pipes2 a and 2 b are fitted on the film frame 5, thereby supporting the photosensitive film 1. As a result, the operator can correct a slack in thecentral portion of the photosensitive film 1 by his hand to load thephotosensitive film 1 without damaging the surface of the photosensitivefilm 1.

[0053] The pipes 2 a and 2 b are fitted on the film frame 5, forexample, with the construction shown in FIG. 5. A leading end portion ofthe flange 11 disposed on the film frame 5 is tapered so as to readilyinsert the pipe 2. Also, the dimensional relation between the innerdiameter D1 of the pipe 2 and the outer diameter D3 of the flange 11 isplaced in tight fit/close fit, thereby making it possible to firmly fitthe pipe 2 to the flange.

[0054] Alternatively, the construction shown in FIG. 5 may be replacedby a construction of FIG. 6. In FIG. 6, reference numeral 2 denotes apipe, 5 is a film frame, 6 is a support roller, 12 is a flange, and 13is a fixing screw.

[0055] The flange 12 has a leading end portion tapered as in the caseshown in FIG. 5 so that the pipe 2 can be readily inserted into theflange 12. Also, the dimensional relation between the inner diameter D1of the pipe 2 and the outer diameter D4 of the flange 14 is placed inclearance fit, thereby making it possible to firmly fit the pipe 2 tothe flange with the screw 13 after the pipe 2 has been inserted into theflange 12.

[0056] (Third Embodiment)

[0057] Still another embodiment of this invention will be describedbelow.

[0058] The constitution of this embodiment is fundamentally the same asshown in FIGS. 4 to 6, but has a feature that a packaging member for usein transporting or storing the film is directly employed as the pipe 2that is the guide member as shown in FIG. 3. As in the case of FIG. 4,the operator corrects a slack in the central portion of thephotosensitive film 1 by his hand to load the photosensitive film 1without damaging the surface of the photosensitive film 1.

[0059] (Fourth Embodiment)

[0060]FIG. 7 is a schematic view showing the structure of a film loaderin an image forming apparatus according to still another embodiment ofthis invention.

[0061] In FIG. 7, reference numeral 1 denotes a photosensitive film, 5is a film frame, 6 a and 6 b are support rollers, and 14 is a guideplate.

[0062] This embodiment shows an example where the work of attaching ordetaching the photosensitive film with respect to the film frame afterthe photosensitive film is removed from the packaging member (forexample, a paper pipe) is conducted.

[0063] In loading the photosensitive film 1, the film frame 5 ishorizontally drawn out from the main body of the image forming apparatusnot shown, the guide plate 14 is fitted onto the film frame 5 as shownin FIG. 7, and thereafter the photosensitive film 1 is loaded into thefilm frame 5 to support the photosensitive film 1. As a result, theoperator can correct a slack in the central portion of thephotosensitive film 1 by his hand to load the photosensitive film 1without damaging the surface of the photosensitive film 1. In thissituation, the guide plate 14 must be surely fitted to the film frame 5.A cross-sectional view of the fitting portion is shown in FIG. 8.

[0064] In FIG. 8, reference numeral 5 denotes a photosensitive film, 6is a support roller, 14 is a guide plate, and 15 is a fixing screw. Theguide plate 14 is firmly fixed to the film frame 5 with the screw 15.

[0065]FIG. 9 is a schematic view showing the structure of a film loaderaccording to still another embodiment of this embodiment. Theconstruction of the guide member is different from that in theabove-mentioned embodiment shown in FIGS. 7 and 8.

[0066] In this example, in loading the photosensitive film 1, the filmframe 5 is horizontally drawn out from the main body of the apparatusnot shown, and the guide 16 is then fitted onto the film frame 5 asshown in FIG. 9. The guide 16 is tapered, and a slack in the centralportion of the photosensitive film 1 is eliminated along the taperedportion of the guide when the operator loads the photosensitive film 1by his hand, thereby loading the photosensitive film 1 without damagingthe surface of the photosensitive film 1. In FIG. 10, reference numeral17 denotes a fixing screw for fixing the guide 16 to the film frame 5.

[0067] As was described above, according to this invention, there can beprovided the film loader for the image forming apparatus in which thefilm can be easily loaded without damaging the film surface.

[0068] The foregoing description of the preferred embodiments of theinvention has been presented for purposes of illustration anddescription. It is not intended to be exhaustive or to limit theinvention to the precise form disclosed, and modifications andvariations are possible in light of the above teachings or may beacquired from practice of the invention. The embodiments were chosen anddescribed in order to explain the principles of the invention and itspractical application to enable one skilled in the art to utilize theinvention in various embodiments and with various modifications as aresuited to the particular use contemplated. It is intended that the scopeof the invention be defined by the claims appended hereto, and theirequivalents.

What is claimed is:
 1. A film loader for an image forming apparatus,comprising: a film frame having a film loading portion for holding afilm formed endlessly; and a guide member for attaching or detaching thefilm with respect to the film loading portion of the film frame, theguide member being formed by a packaging member for use in transportingand storing the film.
 2. The film loader according to claim 1, whereinthe guide member comprises a pipe member having at least two axes whichis detachably attached to the film loading portion of the film frame. 3.The film load according to claim 2, further comprising an adaptorthrough which the pipe member is fixed to the film frame.
 4. The filmload according to any one of claims 1 to 3, wherein the guide member isdetachably attachable with respect to a central portion of the filmloading portion of the film frame.
 5. A film loader for an image formingapparatus, comprising: a film frame having a film loading portion forholding a film formed endlessly; and a guide member having a widthsmaller than that of the film being detachably attachable with respectto the film loading portion of the film frame.
 6. The film loaderaccording to claim 5, wherein the guide member comprises a pipe memberhaving at least two axes which is detachably attached to the filmloading portion of the film frame.
 7. The film loader according to claim5 or 6, wherein the guide member is formed by a packaging member for usein transporting and storing the film.